In a known press of this type, in the case of the introduction of a hard body into the products to be pressed, this hard body, upon pressing, will wedge laterally against the external edge of the blade and the lateral wall of the working bowl, thus blocking the blade and leading to an abnormal heating of the motor which thus can be damaged.
To overcome this risk, it has already been proposed to arrange in the supply circuit of the motor a thermal protective device, for example of the thermostatic detector type, adapted to cut the supply to the motor when the detected temperature exceeds a given threshold. However, such a thermal protective device is particularly costly, sizable and requires precise adjustment which is difficult to obtain.